The present invention relates to a connector for use in connecting and disconnecting fluid carrying conduits such as pipe lines and flow lines for example for use with oil and/or gas, more particularly but not exclusively in subsea locations where for example it is necessary to connect and disconnect such conduits to and from subsea production modules and pipelines.
The increasing use of modularisation for subsea systems has been brought about by the need to reduce subsea installation and maintenance time. The idea of easily interchangeable modules creates a need, therefore, for a suitable "connector". Current connector designs are both costly and complicated, with consequent lack of reliability.
Past and present methods employed in the North Sea have connected/disconnected these modules using multi-datum connections. These methods, which rely on a multitude of alignment datums go against basic engineering design principles, which call for the minimum of datums when connecting/disconnecting two or more components.
Further, to actually connect and disconnect these multi-datum modules, large forces have often been required to spring pipework into alignment, often resulting in the subsequent damage of seals or housings, resulting in production down times. Thermal expansion will also exert undue forces within the connections.
One example of an existing multi-connection subsea module, presently being used in the North Sea consists of approx 20 individual connectors, relying on costly jigs and fixtures to ensure connection integrity. Further, valving is required at each side of the connection for containment of fluids. Basically this means that for each connector interface, a pair of shut-off valves is required which is costly and reduces reliability of the system.
Thus, in Applicant's view, a connector system which does not have the disadvantages of the known multi-connection subsea module has become an essential component in any system of modularisation for subsea oil field development. Previous pressure on the oil companies to look for the new methods of field development has been greatly increased by the recent fluctuations in oil price. The consequence is that, having got over the initial shock, many oil companies are currently planning the next, new series of mainly smaller field developments. These will contain much of the new approach to matters such as modularisation and connections. It is very important, therefore, that a suitable connector will be available to the oil companies.
Another main area identified by the Applicants for use of such a connector is a QCDC (Quick Connect/Disconnect) for a flexible riser system on an FPV (Floating Production Vessel). The flexible riser system between the subsea installation and the FPV requires a connector which provides a connection at the FPV which can be quickly uncoupled or jettisoned in the event of the FPV moving off-station during emergency situations.
Accordingly, the main object of the present invention is to provide a connector which not only overcomes the aforementioned disadvantages of connection/disconnection and the need for external shut-off valves but also provides increased reliability at a price which may be reduced down to as little as approximately a quarter of the price of current connector systems.